Inorganic powder-filled resin composition and formed body

ABSTRACT

Provided are an inorganic substance powder-filled resin composition having uniform dispersibility of inorganic substance powder and providing stable mechanical properties after forming even when the inorganic substance powder is highly filled and a formed article using the inorganic substance powder-filled resin composition. Provided is an inorganic substance powder-filled resin composition including a thermoplastic resin and inorganic substance powder in a mass ratio of 50:50 to 10:90, in which a neutralized product of a polymer made of 50% by mole to 100% by mole of an α,β-unsaturated carboxylic acid and 0% by mole to 50% by mole of another monomer as constitutional units is added. A formed body is prepared using this inorganic substance powder-filled resin composition.

CROSS REFERENCE TO RELATED APPLICATIONS

This is the U.S. national stage of application No. PCT/JP2020/007086,filed on Feb. 21, 2020. Priority under 35 U.S.C. § 119(a) and 35 U.S.C.§ 365(b) is claimed from Japanese Application No. 2019-077391, filed onApr. 15, 2019, the disclosure of which is also incorporated herein byreference.

FIELD

The present invention relates to an inorganic substance powder-filledresin composition and a formed body. More specifically described, thepresent invention relates to an inorganic substance powder-filled resincomposition having excellent dispersibility of inorganic substancepowder and allowing stable mechanical properties to be obtained, inparticular, even in the form of a thin-thickness film and a formed body.

BACKGROUND

Conventionally, thermoplastic resins have been widely used as materialsfor various industrial and household formed bodies, food packaging,formed packaging for general products, and the like together with papermaterials derived from forest resources. However, environmentalprotection becomes an international issue now and thus reduction in theconsumption amount of the thermoplastic resins and paper materials hasbeen significantly studied in parallel with the viewpoint of allowingthe thermoplastic resins and paper materials to be non-toxic,recyclable, and incinerated.

From such a viewpoint, an inorganic substance powder-filled resincomposition formed by highly filling inorganic substance powder into athermoplastic resin has been developed and put into practical use (referto, for example, Patent Literature 1). In particular, calcium carbonateas the inorganic substance powder is a resource that is abundant in thenature and can preferably respond to requirement from the viewpoint ofthe environmental protection.

Incidentally, in the inorganic substance powder-filled resin compositionmade by highly filling the inorganic substance powder into thethermoplastic resin as described above, uniform dispersion of theinorganic substance powder in the thermoplastic resin has beendifficult. In particular, inorganic substance powder having a smallparticle diameter is required to be used in an aspect where a formedarticle is a thin-thickness film such as an inflation film. Theinorganic substance powder having a small particle diameter, however,easily generates agglomeration or the like in the thermoplastic resinand thus causes uneven distribution. Consequently, improvement indispersibility has been required.

Conventionally, several methods have been developed in order to improvethe dispersibility of the inorganic substance powder in the inorganicsubstance powder-filled resin composition as described above.

For example, Patent Literature 2 has developed blend of calciumcarbonate particles having an average particle diameter of 0.1 μm to 0.3μm and subjected to surface treatment with a higher fatty acid such aspalmitic acid and stearic acid or a higher fatty acid salt with respectto 40% by mass to 95% by mass of crystalline polypropylene.

Patent Literature 3 has developed addition of a dispersing agentvesicled by a supercritical reverse phase evaporation method when 30% bymass to 70% by mass of an inorganic filler is blended in an olefin-basedresin and has described use of a higher fatty acid or a higher fattyacid salt as the dispersing agent.

Patent Literature 4 discloses that the water content of calciumcarbonate particles measured between 200° C. and 300° C. by Karl Fischermethod (heat vaporization method) is lowered to 150 ppm or less and thatthe surface is treated with a higher fatty acid or a higher fatty acidsalt.

The various methods such as the surface treatment of the inorganicsubstance powder mainly using the higher fatty acid or the higher fattyacid salt, use of the specific dispersing agent using the supercriticaltechnique, and the selection of calcium carbonate due to fillerproperties have been developed as disclosed in Patent Literature 2 toPatent Literature 4. These methods, however, have problems of, forexample, lowered productivity due to an insufficient dispersion effect,inapplicability of common forming methods, requirement of complicatedprocesses, and the like and thus sufficient solutions have not beenachieved.

With respect to the slurry in which the inorganic substance powder isdispersed in an aqueous medium, different from the system in which theinorganic substance powder is blended in the resin composition, forexample, Patent Literature 5 and Patent Literature 6 have disclosed thata neutralized product of a (co)polymer made of 50% by mole to 100% bymole of an α,β-unsaturated carboxylic acid and 0% by mole to 50% by moleof other monomers is used as a dispersing agent when the slurry in whichan inorganic pigment is dispersed in water is prepared. PatentLiterature 7 discloses that, as the surface treatment of calciumcarbonate particles as an inorganic dispersing agent used at the time ofsuspension polymerization of polystyrene, the calcium carbonateparticles are treated with a (co)polymer containing the α,β-unsaturatedcarboxylic acid as a monomer. In Patent Literature 5 to PatentLiterature 7, however, dispersibility of the inorganic substance powderin the aqueous medium is considered when the (co)polymer containing theα,β-unsaturated carboxylic acid as the monomer or the neutralizedproduct thereof is used. The (co)polymer or the neutralized productthereof is used from the viewpoint of medium affinity between theinorganic substance powder and the aqueous medium, that is, balance ofamphipathicity of hydrophilicity and lipophilicity. Therefore, in thecase of the inorganic substance powder-filled resin composition asdescribed above, it is difficult even for those skilled in the art topredict whether the dispersing agent used in the aqueous mediumcompletely different from the melted thermoplastic resin effectivelyfunctions to the melted thermoplastic resin that is high temperature andhigh viscosity fluid and generally hydrophobic. Considering that thedispersing agent exhibits excellent dispersibility in the aqueousmedium, the dispersing agent is generally conceivable to be difficult touse.

CITATION LIST Patent Literature

-   Patent Literature 1: Japanese Patent Application Laid-open No.    2013-10931-   Patent Literature 2: Japanese Patent Application Laid-open No.    S56-120742-   Patent Literature 3: Japanese Patent Application Laid-open No.    2017-19134-   Patent Literature 4: Japanese Patent Application Laid-open No.    2012-148905-   Patent Literature 5: Japanese Patent Application Laid-open No.    H11-217534-   Patent Literature 6: Japanese Patent Application Laid-open No.    2000-212371-   Patent Literature 7: Japanese Patent Application Laid-open No.    2001-87639

SUMMARY Technical Problem

The present invention has been made in view of the actual situationsdescribed above. An object of the present invention is to provide aninorganic substance powder-filled resin composition having excellentdispersibility of inorganic substance powder, allowing stable mechanicalproperties to be obtained even when the resin composition is formed intothe form of a thin-thickness film, and also having excellent formingprocessability thereof and to provide a formed body.

Solution to Problem

As a result of intensive study for solving the above-described problems,the inventors of the present invention have found that surprisingly, theaddition of a dispersing agent made of a neutralized product of apolymer made of 50% by mole to 100% by mole of an α,β-unsaturatedcarboxylic acid and 0% by mole to 50% by mole of another monomer asconstitutional units to the inorganic substance powder-filled resincomposition made by highly filling the inorganic substance powder intothe thermoplastic resin can significantly improve dispersibility of thecalcium carbonate without affecting other performances. Consequently,the present invention has been attained.

Namely, the present invention solving the above-described problemsincludes an inorganic substance powder-filled resin compositioncomprising: a thermoplastic resin and inorganic substance powder in amass ratio of 50:50 to 10:90, in which a neutralized product of apolymer made of 50% by mole to 100% by mole of an α,β-unsaturatedcarboxylic acid and 0% by mole to 50% by mole of another monomer asconstitutional units is added is represented.

As one aspect of the inorganic substance powder-filled resin compositionaccording to the present invention, the inorganic substancepowder-filled resin composition in which the neutralized product of thepolymer made of 50% by mole to 100% by mole of the α,β-unsaturatedcarboxylic acid and 0% by mole to 50% by mole of the other monomer asthe constitutional units is added in an amount of 3% by mass to 10% bymass relative to the entire composition is represented.

As one aspect of the inorganic substance powder-filled resin compositionaccording to the present invention, the inorganic substancepowder-filled resin composition in which the α,β-unsaturated carboxylicacid is (meth)acrylic acid; and an weight average molecular weight ofthe neutralized product of the polymer made of 50% by mole to 100% bymole of the α,β-unsaturated carboxylic acid and 0% by mole to 50% bymole of the other monomer as the constitutional units is 1,000 to100,000 is represented.

As one aspect of the inorganic substance powder-filled resin compositionaccording to the present invention, the inorganic substancepowder-filled resin composition in which the other polymer is anaromatic ethylenically unsaturated monomer, an alkyl (meth)acrylate,and/or a sulfo group-containing monomer is represented.

As one aspect of the inorganic substance powder-filled resin compositionaccording to the present invention, the inorganic substancepowder-filled resin composition in which the inorganic substance powderis calcium carbonate particles is represented.

As one aspect of the inorganic substance powder-filled resin compositionaccording to the present invention, the inorganic substancepowder-filled resin composition in which an average particle diameter ofthe inorganic substance powder in accordance with an air permeationmethod is 0.5 μm to 13.5 μm is represented.

As one aspect of the inorganic substance powder-filled resin compositionaccording to the present invention, the inorganic substancepowder-filled resin composition in which the inorganic substance powderis not subjected to surface treatment is represented.

Furthermore, the present invention solving the above-described problemsincludes a formed article constituted of an inorganic substancepowder-filled resin composition, the resin composition comprising: athermoplastic resin and inorganic substance powder in a mass ratio of50:50 to 10:90, in which a neutralized product of a polymer made of 50%by mole to 100% by mole of an α,β-unsaturated carboxylic acid and 0% bymole to 50% by mole of another monomer as constitutional units is added.

As one aspect of the formed article according to the present invention,the formed article in which the formed article is an inflation film isrepresented.

Advantageous Effects of Invention

According to the present invention, the resin composition highlyblending the inorganic substance powder allows the highly filledinorganic substance powder to have excellent dispersibility in the resinand the formed body having excellent mechanical properties such astensile strength and elongation to be obtained while moldability isbeing secured. In particular, in the case where the formed body is athin-thickness inflation film, a formed body having excellent mechanicalstrength and excellent appearance properties can be obtained withexcellent moldability.

DESCRIPTION OF EMBODIMENTS

Hereinafter, the present invention will be described in detail withreference to embodiments.

«Inorganic Substance Powder-Filled Resin Composition»

The inorganic substance powder-filled resin composition according to thepresent invention includes the thermoplastic resin and the inorganicsubstance powder in a mass ratio of 50:50 to 10:90 and further includesthe neutralized product of the polymer made of 50% by mole to 100% bymole of the α,β-unsaturated carboxylic acid and 0% by mole to 50% bymole of the other monomer as the constitutional units. Hereinafter, eachcomponent constituting the inorganic substance powder-filled resincomposition according to the present invention will be described indetail.

«Thermoplastic Resim»

The thermoplastic resin that can be used in the inorganic substancepowder-filled resin composition according to the present invention isnot particularly limited. Various types can be used depending on theuse, function, and the like of the composition. Example of thethermoplastic resin include polyolefin-based resins such aspolyethylene-based resins, polypropylene-based resins,polymethyl-1-pentene, and ethylene-cyclic olefin copolymers; functionalgroup-containing polyolefin-based resins such as ethylene-vinyl acetatecopolymers, ethylene-acrylic acid copolymers, ethylene-methacrylic acidcopolymers, metal salts of ethylene-methacrylic acid copolymers(ionomers), ethylene-acrylic acid alkyl ester copolymers,ethylene-methacrylic acid alkyl ester copolymers, maleic acid-modifiedpolyethylene, and maleic acid-modified polypropylene; polyamide-basedresins such as nylon-6, nylon-6,6, nylon-6,10, and nylon-6,12;thermoplastic polyester-based resins including aromatic polyester resinssuch as polyethylene terephthalate and its copolymer, polyethylenenaphthalate, and polybutylene terephthalate and aliphaticpolyester-based resins such as polybutylene succinate and polylacticacid; polycarbonate-based resins including aromatic polycarbonates andaliphatic polycarbonates; polystyrene-based resins such as atacticpolystyrene, syndiotactic polystyrene, acrylonitrile-styrene (AS)copolymers, and acrylonitrile-butadiene-styrene (ABS) copolymers;polyvinyl chloride-based resins such as polyvinyl chloride andpolyvinylidene chloride; polyphenylene sulfides; and polyether-basedresins such as polyethersulfone, polyetherketone, andpolyetheretherketone. These thermoplastic resins can be used singly orin combination of two or more of them.

Of these thermoplastic resins, the polyolefin-based resins, the aromaticpolyester-based resins, and the aliphatic polyester-based resins arepreferably used from the viewpoints of easy formability, performanceaspects, economy aspects, and the like.

Here, the polyolefin-based resins refer to polyolefin-based resinscontaining an olefin component unit as a main component. Specificexamples of the polyolefin-based resins include the polypropylene-basedresin and the polyethylene-based resin as described above, and inaddition polymethyl-1-pentene and ethylene-cyclic olefin copolymers, aswell as a mixture of two or more of these resins. The above phrase “as amain component” means that the olefin component unit is contained in thepolyolefin-based resin in an amount of 50% by mass or more. The contentof the olefin component unit is preferably 75% by mass or more, morepreferably 85% by mass, and further preferably 90% by mass or more. Themethod for producing the polyolefin-based resin used in the presentinvention is not particularly limited. The polyolefin-based resin may beobtained by any of methods using a Ziegler-Natta catalyst, a metallocenecatalyst, oxygen, a radical initiator such as a peroxide, and the like.

Examples of the polypropylene-based resin include resins including apropylene component unit of 50% by mass or more. Examples of the resininclude propylene homopolymers or copolymers of propylene and otherα-olefins copolymerizable with propylene. Examples of the otherα-olefins that can be copolymerized with propylene include α-olefinshaving a carbon number of 4 to 10 such as ethylene, 1-butene,isobutylene, 1-pentene, 3-methyl-1-butene, 1-hexene,3,4-dimethyl-1-butene, 1-heptene, and 3-methyl-1-hexene. As thepropylene homopolymers, any of isotactic polypropylene, syndiotacticpolypropylene, atactic polypropylene, hemiisotactic polypropylene, andlinear or branched polypropylene exhibiting various degrees ofstereoregularities are included. The above copolymer may be a randomcopolymer or a block copolymer and may be not only a binary copolymerbut also a ternary copolymer. Specifically, examples thereof include anethylene-propylene random copolymer, a butene-1-propylene randomcopolymer, an ethylene-butene-1-propylene random ternary copolymer, andan ethylene-propylene block copolymer. The other olefin copolymerizablewith propylene in the above copolymer is preferably contained in a ratioof 25% by mass or less and particularly 15% by mass or less in the casewhere the total mass of the inorganic substance powder-filled resincomposition is determined to be 100% by mass. The lower limit ispreferably 0.3% by mass. These polypropylene-based resins can be usedsingly or in combination of two or more of them.

Examples of the polyethylene-based resin include resins having anethylene component unit of 50% by mass or more. Examples of thepolyethylene-based resin include high-density polyethylene (HDPE),low-density polyethylene (LDPE), medium-density polyethylene, linearlow-density polyethylene (LLDPE), an ethylene-vinyl acetate copolymer,an ethylene-propylene copolymer, an ethylene-propylene-butene-1copolymer, an ethylene-butene-1 copolymer, an ethylene-hexene-1copolymer, an ethylene-4-methylpentene-1 copolymer, an ethylene-octene-1copolymer, and a mixture of two or more of these resins.

Polyethylene having a density of 0.942 g/cm³ or more is usually referredto as “high-density polyethylene (HDPE)”, polyethylene having a densityof 0.930 g/cm³ or more and less than 0.942 g/cm³ is usually referred toas “medium-density polyethylene”, polyethylene having a density of 0.910g/cm³ or more and less than 0.930 g/cm³ is usually referred to as“low-density polyethylene (LDPE)”, and polyethylene having a density ofless than 0.910 g/cm³ is usually referred to as “ultra-low-densitypolyethylene (ULDPE)”. “Linear low-density polyethylene (LLDPE)” usuallyhas a density of 0.911 g/cm³ or more and less than 0.940 g/cm³ andpreferably a density of 0.912 g/cm³ or more and less than 0.928 g/cm³.

Of the above-described polyolefin-based resins, the polypropylene-basedresins are preferably used because they have a particularly excellentbalance between mechanical strength and heat resistance.

«Inorganic Substance Powder»

The inorganic substance powder that can be blended in the inorganicsubstance powder-filled resin composition according to the presentinvention is not particularly limited. Examples of the inorganicsubstance powder include powder carbonates, sulfates, silicates,phosphates, borates, and oxides of calcium, magnesium, aluminum,titanium, iron, zinc, and the like, or hydrates thereof. Specificexamples of the inorganic substance powder include calcium carbonate,magnesium carbonate, zinc oxide, titanium oxide, silica, alumina, clay,talc, kaolin, aluminum hydroxide, magnesium hydroxide, aluminumsilicate, magnesium silicate, calcium silicate, aluminum sulfate,magnesium sulfate, calcium sulfate, magnesium phosphate, barium sulfate,silica sand, carbon black, zeolite, molybdenum, diatomaceous earth,sericite, shirasu, calcium sulfite, sodium sulfate, potassium titanate,bentonite, and graphite. These inorganic substance powders may besynthetic products or products originated from minerals. These inorganicsubstance powders may be used singly or in combination of two or more ofthem.

The shape of the inorganic substance powder is not particularly limitedand may be any of a particle shape, a flake shape, a granule shape, anda fiber shape. The particle shape may be a spherical shape so as to begenerally obtained by a synthesis method or an irregular shape so as tobe obtained by pulverizing collected natural minerals.

As the inorganic substance powder, calcium carbonate, magnesiumcarbonate, zinc oxide, titanium oxide, silica, alumina, clay, talc,kaolin, aluminum hydroxide, magnesium hydroxide, and the like arepreferable and calcium carbonate is particularly preferable. The calciumcarbonate may be both of what is called light calcium carbonate preparedby a synthesis method and what is called heavy calcium carbonateobtained by mechanically pulverizing and classifying a natural rawmaterials including CaCO₃ as the main component such as limestone andthe combination of these is also applicable. From the viewpoint ofeconomic efficiency, the heavy calcium carbonate is preferable.

Here, the heavy calcium carbonate is a product obtained by mechanicallypulverizing and processing natural limestone or the like and is clearlydistinguished from synthetic calcium carbonate produced by chemicalprecipitate reaction or the like. The pulverizing method includes a drymethod and a wet method. From the viewpoint of economic efficiency, thedry method is preferable.

The heavy calcium carbonate particles is different from, for example,light calcium carbonate produced by the synthesis method and ischaracterized by irregular shape properties of the surface and highspecific surface area due to particle formation performed by pulverizingtreatment. Due to the irregular shape properties of the surface and highspecific surface area of the heavy calcium carbonate particles asdescribed above, the heavy calcium carbonate particles have more contactinterfaces with the thermoplastic resin in the case where the heavycalcium carbonate particles are blended in the thermoplastic resin andthus provide the effect of uniform dispersion.

Although not particularly limited, the specific surface area of theheavy calcium carbonate particles, which is dependent on the averageparticle diameter of the heavy calcium carbonate, is desirably about3,000 cm²/g or more and about 35,000 m²/g or less. Here, the specificsurface area is determined in accordance with an air permeation method.With respect to the formed article to be obtained, the heavy calciumcarbonate particles having the specific surface area within this rangetend to reduce deterioration in processability of the resin compositiondue to the blend of the heavy calcium carbonate particles.

The irregular shape properties of the heavy calcium carbonate particlescan be represented by the low degree of spheroidization of the particleshape. Although not particularly limited, specifically, the roundness is0.50 or more and 0.95 or less, more preferably 0.55 or more and 0.93 orless, and further preferably 0.60 or more and 0.90 or less. The heavycalcium carbonate particles having the roundness within this range allowthe strength as the product and forming processability to be appropriatein the case where the heavy calcium carbonate particles are blended intothe thermoplastic resin to form the formed article.

Here, the roundness can be represented by (Projected area ofparticle)/(Area of a circle having the same perimeter as the projectedperimeter of particle). The method for measuring the roundness is notparticularly limited. For example, the projected area of the particleand the projected perimeter of the particle are measured from amicrograph and determined to be (A) and (PM), respectively. When theradius of a circle having the same perimeter as the projected perimeterof the particle is determined to be (r),

PM=2πr  (1).

When the area of the circle having the same perimeter as the projectedperimeter of the particle is determined to be (B),

B=πr ²  (2).

Transforming Formula (1) results in

r=PM/2π  (3).

Therefore, substituting Formula (3) into Formula (2) results in

B=π×(PM/2π)²  (4).

Therefore, the roundness is determined as Roundness=A/B=A×4π/(PM)².The particles to be measured are sampled so as to represent the particlediameter distribution of the powder. As the number of the measuredparticles becomes larger, the measured value becomes more reliable. Inconsideration of the measurement time also, the roundness is said to bedetermined by the average value of about 100 particles. Also in thepresent specification, the average value of 100 particles is used. Thesemeasurements are performed with generally commercially available imageanalysis software using the projection image of each particle obtainedby a scanning microscope, a stereomicroscope, or the like, whereby theroundness can be determined.

In order to enhance the dispersibility of the inorganic substance powderin the thermoplastic resin, the surface of the calcium carbonateparticles may be previously modified in accordance with the commonmethods. Examples of the surface modification method include a method ofphysical treatment such as plasma treatment and a method of chemicaltreatment of the surface with a coupling agent or a surfactant. Examplesof the coupling agent include a silane coupling agent and a titaniumcoupling agent. As the surfactant, any of an anionic surfactant, acationic surfactant, a nonionic surfactant, and an amphoteric surfactantmay be used. Examples of the surfactant include a higher fatty acid, ahigher fatty acid ester, a higher fatty acid amide, and a higher fattyacid salt.

In the preferable embodiment of the present invention, as the inorganicsubstance powder to be used, however, inorganic substance powder that isnot subjected to the surface treatment using the chemical treatmentagent, or at least not subjected to the surface treatment with the fattyacid-based compound as described above are preferably used.

In the present invention, this is because the neutralized product of thepolymer made of 50% by mole to 100% by mole of the α,β-unsaturatedcarboxylic acid and 0% by mole to 50% by mole of the other monomer asthe constitutional units described in detail below is separately blendedas the dispersing agent, whereby sufficient uniform dispersibility ofthe inorganic substance powder can be achieved, and thus on thecontrary, uniform dispersibility may deteriorate by subjecting thesurface of the inorganic substance powder to the surface treatment withthe chemical treatment agent, in particular, the fatty acid-basedcompound. In addition, this is because use of the calcium carbonateparticles not subjected to the surface treatment as described aboveallows the cause of odor due to the thermal decomposition of the surfacetreatment agent attached to the inorganic substance powder surface atthe time of forming to be slightly eliminated. Therefore, as aparticularly preferable embodiment of the present invention, use of theheavy calcium carbonate not subjected to the surface treatment as theinorganic substance powder to be used is included.

The inorganic substance powder is preferably particles. The averageparticle diameter is preferably 0.1 μm or more and 50.0 μm or less andmore preferably 1.0 μm or more and 15.0 μm or less.

Although not particularly limited, in the case where the inorganicsubstance powder is the calcium carbonate particles, the averageparticle diameter is preferably within a range of 0.5 μm or more and13.5 μm or less and more preferably 0.7 μm or more and 6.0 μm or less.

The average particle diameter of the inorganic substance powder or thecalcium carbonate particles described in the present specificationrefers to a value calculated from the measurement result of the specificsurface area by the air permeation method in accordance with JIS M 8511.As a measurement device, for example, a specific surface areameasurement apparatus Type SS-100 manufactured by SHIMADZU CORPORATIONcan be preferably used.

In particular, the particles having a particle diameter of more than50.0 μm are preferably excluded in the particle diameter distribution ofthe inorganic substance powder. On the other hand, excessively fineparticles cause the viscosity at the time of kneading with the abovethermoplastic resin to be significantly increased and thus theproduction of the formed body may be difficult. Therefore, the averageparticle diameter of the inorganic substance powder is preferablydetermined to be 0.5 μm or more.

The average particle diameter of the inorganic substance powder havingthe powder shape, the flake shape, or the granule shape is preferably10.0 μm or less and more preferably 5.0 μm or less.

The average fiber length of the inorganic substance powder having thefiber shape is preferably 3.0 μm or more and 20.0 μm or less. Theaverage fiber diameter is preferably 0.2 μm or more and 1.5 μm or less.The aspect ratio is usually 10 or more and 30 or less. The average fiberlength and the average fiber diameter of the inorganic substance powderhaving the fiber shape are measured by observation using an electronmicroscope and the aspect ratio is a ratio of the average fiber lengthto the average fiber diameter (Average fiber length/Average fiberdiameter).

The blend ratio of the thermoplastic resin and the inorganic substancepowder (% by mass) included in the inorganic substance powder-filledresin composition according to the present invention is not particularlylimited as long as the ratio is 50:50 to 10:90. The ratio is preferablyin a ratio of 40:60 to 20:80 and preferably in a ratio of 40:60 to25:75. This is because, in the blend ratio of the thermoplastic resinand the inorganic substance powder, given texture and physicalproperties such as impact resistance of the inorganic substancepowder-filled resin composition provided by blending the inorganicsubstance powder are not obtained in the case where the ratio of theinorganic substance powder is less than 50% by mass, whereas formingprocess by, for example, extrusion forming, inflation molding, andvacuum forming is difficult in the case where the ratio of the inorganicsubstance powder is more than 90% by mass.

«Dispersing agent»

In the inorganic substance powder-filled resin composition, theneutralized product of the polymer made of 50% by mole to 100% by moleof the α,β-unsaturated carboxylic acid and 0% by mole to 50% by mole ofthe other monomer as the constitutional units is included as thedispersing agent, in addition to the above-described thermoplastic resinand inorganic substance powder.

(α,β-Unsaturated Carboxylic Acid)

Examples of the α,β-unsaturated carboxylic acid serving as the mainconstitutional unit of this polymer include α,β-unsaturated carboxylicacids or anhydrides thereof such as acrylic acid, methacrylic acid,crotonic acid, maleic acid, maleic anhydride, fumaric acid, itaconicacid, itaconic anhydride, citraconic acid, citraconic anhydride, halfesters of maleic acid (for example, maleic acid monobutyl ester andmaleic acid monoethyl carbitol ester), half esters of fumaric acid (forexample, fumaric acid monobutyl ester and fumaric acid monoethylcarbitolester), or any combination of two or more of them.

Of these compounds, in particular, acrylic acid, methacrylic acid,itaconic acid, maleic acid, fumaric acid, half esters of maleic acid,and half esters of fumaric acid are preferable and acrylic acid andmethacrylic acid are more preferable.

(Other Monomers)

The polymer may contain other monomer copolymerizable with theα,β-unsaturated carboxylic acid as the constitutional unit of thepolymer. Examples of the other monomer include, but are not limited tothe following substances.

(a) Aromatic ethylenically unsaturated monomers: Styrenes such asstyrene, α-methylstyrene, vinyltoluene, and hydroxystyrene, halogensubstituents of styrenes such as dichlorostyrene, vinylnaphthalene, andthe like;

(b) Aliphatic ethylenically unsaturated monomer having a carbon numberof 2 to 20: Ethylene, propylene, butene, isobutylene, pentene, heptene,diisobutylene, octene, dodecene, octadecene, butadiene, isoprene, andthe like;

(c) Alicyclic ethylenically unsaturated monomer having a carbon numberof 5 to 15: Cyclopentadiene, pinene, limonene, indene,bicyclopentadiene, ethylidene norbornene, and the like;

(d) Alkyl (meth)acrylate having an alkyl group having a carbon number of1 to 50: Methyl (meth)acrylate, ethyl (meth)acrylate, propyl(meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate,dodecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl(meth)acrylate, eicosyl (meth)acrylate, and the like;

(e) Hydroxy group-containing (meth)acrylate: Hydroxyethyl(meth)acrylate, hydroxypropyl (meth)acrylate, and the like;

(f) Amide-containing ethylenically unsaturated monomer:(Meth)acrylamide, N-methylol (meth)acrylamide, and the like;

(g) Ethylenically unsaturated monomer having a polyalkylene glycol chain(molecular weight of 44 to 2,000): Polyethylene glycol (molecular weightof 300) mono(meth)acrylate, polypropylene glycol (molecular weight of500) mono(meth)acrylate, methyl alcohol ethylene oxide 10-mol adduct(meth)acrylate, lauryl alcohol ethylene oxide 30-mol adduct(meth)acrylate, and the like;

(h) Sulfo group-containing monomer: Vinyl sulfonic acid,(meth)allylsulfonic acid, 2-hydroxy-3-(meth)allyloxypropanesulfonicacid, styrenesulfonic acid, α-methylstyrene sulfonic acid, sulfopropyl(meta)acrylate, 2-hydroxy-3-(meth)acryloyloxypropanesulfonic acid,2-(meth)acryloylamino-2,2-dimethylethanesulfonic acid,3-(meth)acryloyloxyethanesulfonic acid,3-(meta)acryloyloxy-2-hydroxypropanesulfonic acid,2-(meth)acrylamide-2-methylpropanesulfonic acid,3-(meth)acrylamide-2-hydroxypropanesulfonic acid, alkyl (carbon numberof 3 to 18) (meth)allylsulfosuccinic acids, sulfate esterified productsof poly (n=2 to 30) oxyalkylene mono(meth)acrylates (the oxyalkylene isan oxyalkylene having a carbon number of 2 to 4 and may be a homo,random, or block) [for example, a poly (n=5 to 15) oxypropylenemonomethacrylate sulfate esterified product, and the like], and othercompounds represented by the following general formulas (I), (II), and(III).

(In the formula, R represents an alkyl group having a carbon number of 1to 15; A represents an alkylene group having a carbon number of 2 to 4,in the case where n is plural, “A”s may be the same as or different fromeach other, and in the case where “A”s are different from each other,“A” may be random or block; Ar represents a benzene ring; and nrepresents an integer of 1 to 50.)

(In the formula, R represents an alkyl group having a carbon number of 1to 15; A represents an alkylene group having a carbon number of 2 to 4,in the case where n is plural, “A”s may be the same as or different fromeach other, and in the case where “A”s are different from each other,“A”s may be random or block; Ar represents a benzene ring; and nrepresents an integer of 1 to 50.)

(In the formula, R′ represents an alkyl group having a carbon number of1 to 15 and optionally substituted with a fluorine atom.)

In the polymer, the content of the α,β-unsaturated carboxylic acid asthe constitutional unit is usually 50% by mole to 100% by mole andpreferably 70% by mole to 100% by mole. On the other hand, the contentof the other monomer is usually 0% by mole to 50% by mole and preferably0% by mole to 30% by mole. Namely, the α,β-unsaturated carboxylic acidas the constitutional unit having the content in the range of 50% bymole to 100% by mole allows an effective action to the dispersibility ofthe inorganic substance powder in the thermoplastic resin to beexhibited in the inorganic substance powder-filled resin composition.

Here, the other monomer is not limited to one kind and a plurality ofkinds of monomers may be used. In addition, a copolymer made of aternary component or a multinary component may be used. As describedabove, in the case where a plurality of kinds of monomers are used asthe other monomers, the content of the other monomers described above isthe total amount of such other monomers.

In the aspect in which the polymer is made by copolymerizing theα,β-unsaturated carboxylic acid with the other monomer as describedabove, the preferable other monomer depends on the kinds of theabove-described thermoplastic resin included in the inorganic substancepowder-filled resin composition. Generally, the other monomer ispreferably a monomer that is the same kind as or a similar kind to themonomer constituting the thermoplastic resin.

Furthermore, of the other monomers, (a), (b), (d), (e), (g), and (h) arepreferable, and (a), (d), and (h) are particularly preferable. In thepresent invention, the acid group is usually a carboxylic acid group. Inthe case where (h) is used as the copolymerization component, however,the acid groups are the carboxylic acid group and the sulfonic acidgroup. The acid group as the monomer may be neutralized with an alkalimetal, an alkaline earth metal, or an organic amine.

In the aspect in which the polymer is made by copolymerizing theα,β-unsaturated carboxylic acid with the other monomer as describedabove, the polymer may have any sequence such as a random copolymer, ablock copolymer, a graft copolymer, or an alternating copolymer. Ofthese copolymers, copolymers in the form of the block copolymer and thegraft copolymer are particularly desirable.

Although not particularly limited, the weight average molecular weightof the polymer is usually 1,000 to 100,000. The weight average molecularweight is preferably 5,000 to 30,000 and the molecular weightdistribution is usually 1.10 to 4.50 and preferably 1.1 to 2.5.

In the present invention, the neutralized product of the polymer is usedas the dispersing agent. The degree of neutralization of the neutralizedproduct is desirably at least 0.20 or more and more preferably 0.25 to1.00. The neutralized product in which the acid groups in the polymerare neutralized to some extent or more as described above allows thedispersibility of the inorganic substance powder in the thermoplasticresin in which the neutralized product of the polymer is blended to beexcellent.

Such a neutralized product can be obtained by using a monomer obtainedby neutralizing the acid group (usually a carboxylic acid group) in themonomer to polymerize or subjecting the polymer to neutralizationtreatment after the polymer is obtained as described below.

In a preferable aspect, 18.8% by mole to 99.9% by mole and preferably25.0% by mole to 99.9% by mole of the acid groups in the polymer are analkali metal salt or an alkaline earth metal salt except a magnesiumsalt, 0.1% by mole to 1.2% by mole and preferably 0.6% by mole to 1.1%by mole of the acid groups are a magnesium salt, and 0% by mole to 80.0%by mole of the acid groups are free acid groups. In such an aspect,examples of the alkali metal include lithium, sodium, and potassium. Insuch an aspect, examples of the alkaline earth metal include calcium andbarium.

In another preferable aspect, 10.0% by mole to 99.9% by mole, preferably15.0% by mole to 94.9% by mole, and particularly preferably 20.0% bymole to 80.0% by mole of the acid groups in the polymer are an alkalimetal salt or an alkaline earth metal salt, 0% by mole to 5.0% by mole,preferably 0% by mole to 4.0% by mole, and particularly preferably 0.1%by mole to 2.0% by mole of the acid groups are an organic amine salt,and 0% by mole to 90.0% by mole, preferably 5.0% by mole to 85.0% bymole, and particularly preferably 20.0% by mole to 80.0% by mole of theacid groups are free acid groups. In such an aspect, examples of thealkali metal include lithium, sodium, and potassium. In such an aspect,examples of the alkaline earth metal include calcium, magnesium, andbarium.

Examples of the organic amine include aliphatic (primary, secondary, andtertiary) amines, alicyclic amines, aromatic amines, alkylene oxideadducts of the primary or secondary amines, and (poly)alkylenepolyamines. Examples of the aliphatic amines include alkylamines havingan alkyl group having a carbon number of 1 to 20. Examples of theprimary amine include methylamine, ethylamine, n-butylamine, octylamine,decylamine, dodecylamine, tetradecylamine, hexadecylamine,octadecylamine, palm alkylamines, beef fat alkylamines, cured beef fatalkylamines, oleylamine, and soybean alkylamines. Examples of thesecondary amines include dimethylamine, diethylamine, dibutylamine,dioctylamine, didecylamine, didodecylamine, ditetradecylamine,dihexadecylamine, dioctadecylamine, dioleylamine, dipalm alkylamines,and di-cured beef fat alkyl amines Examples of the tertiary aminesinclude trimethylamine, triethylamine, tri-n-propylamine,tri-n-butylamine, diethyl-1-propylamine, octyldimethylamine,decyldimethylamine, dodecyldimethylamine, tetradecyldimethylamine,hexadecyldimethylamine, and octadecyldimethylamine Examples of thealicyclic amine include cycloalkylamines having a cycloalkyl group andspecific examples thereof include cyclopentylamine, cyclohexylamine,pyrrolidine, purine, dicyclohexylamine, cyclohexylmethylamine, N-methylpyrrolidine, N-ethyl pyrrolidine, N-methyl piperidine, N-ethylpiperidine, N-methyl hexamethylene imine, N-ethyl hexamethylene imine,N-methyl morpholine, N-butyl morpholine,1,5-diazabicyclo[4,3,0]-5-nonene, and1,8-diazabicyclo[5,4,0]-7-undecene. Examples of the aromatic amineinclude aniline, benzylamine, toluidine, benzidine, pyrimidine,N,N-dimethylaniline, phenylenediamine (o, m, p), pyridine,4-methylbenzimidazole, quinoline, and 4,4′-dipyridyl. Examples of thealkylene oxide of the alkylene oxide adduct of the primary or secondaryamine include ethylene oxide, propylene oxide, and butylene oxide. Thenumber of addition moles in these adducts is usually 1 mol to 5 mol andpreferably 1 mol to 2 mol per active hydrogen. Specific examples thereofinclude a propylene oxide 2-mol adduct of cyclohexylamine and apropylene oxide 1 mol-adduct of dioctylamine Examples of the(poly)alkylene polyamine include ethylenediamine, diethylenetriamine,triethylenetetramine, tetraethylenepentamine, and alkylated productsthereof. Of the organic amines, the aliphatic or alicyclic amines or thealkylene oxide adducts thereof are preferable.

In order to obtain the neutralized product of the polymer byneutralization treatment after the polymerization of the polymer, forexample, the polymer is neutralized with an alkali metal hydroxide, analkaline earth metal hydroxide, an amine compound, or the like in anappropriate order so that the acid groups in the polymer are in a stateof the salt and the free acid in a given ratio in the above-describedpreferable aspect, whereby the neutralized product of the polymer can beobtained. The neutralized product of the polymer can also be prepared byblending each separately prepared product in a state of the salt and thefree acid in a given ratio.

For example, in the case where the polymer is the polymer described inthe above preferable aspect, the neutralized product of the polymer canbe obtained by neutralizing the polymer with an aqueous solution of analkali metal hydroxide (for example, sodium hydroxide or potassiumhydroxide) or a hydroxide of an alkaline earth metal except magnesium(for example, barium hydroxide or calcium hydroxide) and thereafterneutralizing with magnesium hydroxide so that 18.8% by mole to 99.9% bymole of the acid groups in the polymer are converted into the alkalimetal salt or the salt of the alkaline earth metal except magnesium,0.1% by mole to 1.2% by mole of the acid groups are converted into themagnesium salt, and 0% by mole to 80.0% by mole of the acid groupsremain free acid groups.

In addition, for example, in the case where the polymer is the polymerdescribed in another preferable aspect described above, the neutralizedproduct of the polymer can be obtained by neutralizing the polymer withan aqueous solution of an alkali metal hydroxide (for example, sodiumhydroxide or potassium hydroxide) or an alkaline earth metal hydroxide(for example, magnesium hydroxide or calcium hydroxide) and thereafterneutralizing with the organic amine so that 10.0% by mole to 100% bymole of the acid groups in the polymer are converted into the alkalimetal salt or the alkaline earth metal salt, 0% by mole to 5.0% by moleof the acid groups are converted into the organic amine salt, and 0% bymole to 90.0% by mole of the acid groups remain free acid groups.

In the inorganic substance powder-filled resin composition according tothe present invention, the neutralized product of the polymer made of50% by mole to 100% by mole of the α,β-unsaturated carboxylic acid and0% by mole to 50% by mole of the other monomer as the constitutionalunits is preferably added in 3% by mass to 10% by mass and morepreferably 5% by mass to 8% by mass relative to the entire composition.This is because the inorganic substance powder-filled resin compositionhaving the amount to be added within such a range allows thedispersibility of the inorganic substance powder in the thermoplasticresin to be excellent and on the other hand does not provide an adverseeffect to other physical, chemical, and functional properties.

«Other Additives»

To the inorganic substance powder-filled resin composition according tothe present invention, other additives can be blended as auxiliaryagents, if necessary. As the other additives, for example, colorants,lubricating agents, coupling agents, flowability improvers,antioxidants, ultraviolet ray absorbers, flame retardants, stabilizers,antistatic agents, plasticizers, and the like may be blended. Theseadditives may be used singly or in combination of two or more of them.These additives may be blended at the kneading process described belowor may be previously blended to the inorganic substance powder-filledresin composition before the kneading process. In the inorganicsubstance powder-filled resin composition according to the presentinvention, the amount of these other additives to be added is notparticularly limited as long as the given effect by the blend of theabove the neutralized product of the polymer made of 50% by mole to 100%by mole of the α,β-unsaturated carboxylic acid and 0% by mole to 50% bymole of the other monomer as the constitutional units in addition to theabove thermoplastic resin and inorganic substance powder is notimpaired. For example, each of these other additives is desirablyblended in a ratio of about 0% by mass to about 5% by mass and the ratioof the entire other additives is desirably 10% by mass or less in thecase where the mass of the entire inorganic substance powder-filledresin composition is determined to be 100% by mass.

Hereinafter, the additives considered to be important in these additiveswill be described with reference to examples. The additives, however,are not limited to the additives exemplified below at all.

As the colorants, any of the known organic pigments, inorganic pigments,or dyes may be used. Specific examples include organic pigments such asazo-based, anthraquinone-based, phthalocyanine-based,quinacridone-based, isoindolinone-based, dioxazine-based,perinone-based, quinophthalone-based, and perylene-based pigments andinorganic pigments such as ultramarine blue, titanium oxide, titaniumyellow, iron oxide (red iron oxide), chromium oxide, zinc white, andcarbon black.

Examples of the lubricating agents include fatty acid-based lubricatingagents such as stearic acid, hydroxystearic acid, complex stearic acid,and oleic acid; aliphatic alcohol-based lubricating agents; aliphaticamide-based lubricating agents such as stearoamide, oxystearamide,oleylamide, erucylamide, ricinolamide, behenamide, methylolamide,methylenebisstearamide, methylenebisstearobehenamide, higher fatty acidbisamides, and complex amides; aliphatic ester-based lubricating agentssuch as n-butyl stearate, methyl hydroxystearate, polyhydric alcoholfatty acid esters, saturated fatty acid esters, and ester-based wax; andfatty acid metal soap-based lubricating agents.

As the antioxidants, phosphorous-based antioxidants, phenol-basedantioxidants, and pentaerythritol-based antioxidants may be used. Thephosphorous-based antioxidants, more specifically, phosphorous-basedantioxidants such as phosphite esters and phosphate esters arepreferably used. Examples of the phosphites include triesters, diesters,and monoesters of phosphorous acid such as triphenyl phosphite,trisnonylphenyl phosphite, and tris(2,4-di-t-butylphenyl)phosphite.

Examples of the phosphate esters include trimethyl phosphate, triethylphosphate, tributyl phosphate, trioctyl phosphate, triphenyl phosphate,tricresyl phosphate, tris(nonylphenyl) phosphate, and 2-ethylphenyldiphenyl phosphate. These phosphorous-based antioxidants may be usedsingly or in combination of two or more of them.

Examples of the phenol-based antioxidants include α-tocopherol,butylhydroxytoluene, sinapyl alcohol, vitamin E,n-octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl) propionate,2-t-butyl-6-(3′-t-butyl-5′-methyl-2′-hydroxybenzyl)-4-methylphenylacrylate, 2,6-di-t-butyl-4-(N,N-dimethylaminomethyl)phenol,3,5-di-t-butyl-4-hydroxybenzylphosphonate diethyl ester, andtetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxymethyl]methane.These phenol-based antioxidants may be used singly or in combination oftwo or more of them.

The flame retardant is not particularly limited. For example, ahalogen-based flame retardant or a non-halogen-based flame retardantsuch as a phosphorus-based flame retardant and a metal hydrate may beused. Specific examples of the halogen-based flame retardant include ahalogenated bisphenol-based compound such as a halogenatedbisphenylalkane, a halogenated bisphenyl ether, a halogenated bisphenylthioether, and a halogenated bisphenyl sulfone and abisphenol-bis(alkylether)-based compound such as brominated bisphenol A,brominated bisphenol S, chlorinated bisphenol A, and chlorinatedbisphenol S. Specific examples of the phosphorus-based flame retardantinclude aluminum tris(diethylphosphinate),bisphenol-A-bis-(diphenylphosphate), tri(isopropylated aryl) phosphates,cresyl-di-2,6-xylenyl phosphate, and an aromatic condensed phosphate.Specific examples of the metal hydrate include aluminum trihydrate,magnesium dihydroxide, and combination thereof. These flame retardantsmay be used singly or in combination of two or more of them. Inaddition, for example, antimony oxides such as antimony trioxide andantimony pentoxide, zinc oxide, iron oxide, aluminum oxide, molybdenumoxide, titanium oxide, calcium oxide, magnesium oxide, or the like canbe used together as a flame retardant auxiliary.

The foaming agent is mixed or injected with pressure in the inorganicsubstance powder-filled resin composition serving as the raw material ina melted state in a melting kneader and is a substance that causes phasechange from solid to gas or from liquid to gas or a substance that isgas itself. The foaming agent is mainly used for controlling the foamingratio (foam density) of the foam sheet. As the foaming agent dissolvedin the inorganic substance powder-filled resin composition serving asthe raw material, the phase of a foaming agent that is liquid at normaltemperature is changed into gas due to the temperature of the resin todissolve in the melted resin and the phase of a foaming agent that isgas at normal temperature is not changed and the foaming agent isdissolved in the melted resin as it is. The foaming agent dispersed anddissolved in the melted resin expands inside a sheet at the time ofextruding the melted resin from an extrusion die in a sheet-like formbecause the pressure is released and thus many fine closed cells areformed in the sheet to provide a foam sheet. The foaming agent acts as aplasticizer as a side effect that reduces the melt viscosity of the rawmaterial resin composition and lowers the temperature for making the rawmaterial resin composition in a plasticized state.

Examples of the foaming agent include aliphatic hydrocarbons such aspropane, butane, pentane, hexane, and heptane; alicyclic hydrocarbonssuch as cyclobutane, cyclopentane, and cyclohexane; halogenatedhydrocarbons such as chlorodifluoromethane, difluoromethane,trifluoromethane, trichlorofluoromethane, dichloromethane,dichlorofluoromethane, dichlorodifluoromethane, chloromethane,chloroethane, dichlorotrifluoroethane, dichloropentafluoroethane,tetrafluoroethane, difluoroethane, pentafluoroethane, trifluoroethane,dichlorotetrafluoroethane, trichlorotrifluoroethane,tetrachlorodifluoroethane, and perfluorocyclobutane; inorganic gas suchas carbon dioxide, nitrogen, and air; and water.

As the foaming agent, for example, a compound in which the activecomponent of the foaming agent is contained in a carrier resin is alsopreferably used. Examples of the carrier resin include a crystallineolefin resin. Of these carrier resins, a crystalline polypropylene resinis preferable. Examples of the active component include hydrogencarbonates. Of these compounds, the hydrogen carbonates are preferable.The compound is preferably a foaming agent concentrate including thecrystalline polypropylene resin as the carrier resin and the hydrogencarbonate as the thermally decomposable foaming agent.

The content of the foaming agent included in the foaming agent in theforming process can be appropriately determined depending on the kindsof the thermoplastic resin and inorganic substance powder, and aquantity of the active component. The content is preferably determinedto be in the range of 0.04% by mass to 5.00% by mass in the case wherethe total mass of the inorganic substance powder-filled resincomposition is determined to be 100% by mass.

In the aspect in which the inorganic substance powder-filled resincomposition according to the present invention includes the foamingagent, the mass ratio (% by mass) of two components of the thermoplasticresin and the foaming agent is more preferably in a ratio of 80:20 to98:2 and the ratio of 80:20 to 90:10 can be exemplified as a preferableexample.

«Method for Producing Inorganic Substance Powder-Filled ResinComposition»

In the method for producing the inorganic substance powder-filled resincomposition according to the present invention, common methods can beused. The method may be appropriately determined depending on theforming method (for example, extrusion forming, injunction forming, anda vacuum forming). For example, the thermoplastic resin, the inorganicsubstance powder, the neutralized product of the polymer made of 50% bymole to 100% by mole of the α,β-unsaturated carboxylic acid and 0% bymole to 50% by mole of the other monomer as the constitutional units,and, if necessary, other additives may be kneaded and melted before thematerials are fed from a hopper to a forming machine or these materialsmay be integrally and simultaneously kneaded and melted with formingusing a forming machine. Before adding the inorganic substance powderinto the thermoplastic resin, the neutralized product of the polymermade of 50% by mole to 100% by mole of the α,β-unsaturated carboxylicacid and 0% by mole to 50% by mole of the other monomer as theconstitutional units and the inorganic substance powder may be subjectedto mixing treatment. Alternatively, in contrast, the neutralized productof the polymer made of 50% by mole to 100% by mole of theα,β-unsaturated carboxylic acid and 0% by mole to 50% by mole of theother monomer as the constitutional units and the thermoplastic resinmay be subjected to the mixing treatment. The kneading and melting arepreferably carried out by applying high shear stress to the kneadingwhile the inorganic substance powder is being uniformly dispersed in thethermoplastic resin and preferably carried out using, for example, atwin-screw kneader to knead.

In the method for producing the inorganic substance powder-filled resincomposition according to the present invention, the inorganic substancepowder-filled resin composition may be in the form of pellets or may bedifferent from the form of pellets. In the case where the thermoplasticresin composition is in the form of pellets, the shape of the pellets isnot particularly limited. For example, pellets having a cylindricalshape, a spherical shape, an elliptical sphere shape, or the like may beformed.

The size of the pellets may be appropriately determined depending on theform. For example, in the case of the spherical pellets, the diametermay be 1 mm to 10 mm. In the case of the elliptical sphere shapepellets, the pellets may be an elliptical sphere shape having a ratio ofa longitudinal length and a transverse length of 0.1 to 1.0 and alongitudinal and transverse size of 1 mm to 10 mm. In the case ofcylindrical pellets, the pellets may have a diameter in the range of 1mm to 10 mm and a length in the range of 1 mm to 10 mm. These shapes maybe formed to the pellets after the kneading process described below. Theshape of the pellets may be formed in accordance with the commonmethods.

(Formed Article)

The formed article according to the present invention is a formedarticle formed by using the inorganic substance powder-filled resincomposition.

The shape and the like of the formed article according to the presentinvention are not particularly limited. The shape may be various formsand the formed article may be formed as various formed articles such asa sheet or a film, a container for food, and other container body.

The thickness of the formed article according to the present inventionis not particularly limited and may be various thickness from athin-thickness to a thick thickness depending on the form of the formedarticle. For example, the formed article preferably having a thicknessof 40 μm or more and 5,000 μm or less and more preferably having athickness of 50 μm or more and 1,000 μm or less is exhibited. The formedarticle having the thickness within the range allows the formed articlehaving no problems of formability and processability, not causing uneventhickness, being uniform, and having no defect to be formed due touniform dispersion of the inorganic substance powder in thethermoplastic resin.

In particular, in the case where the form of the formed article is asheet, the thickness of the sheet is desirably more preferably 50 μm to1,000 μm and further preferably 50 μm to 400 μm. The sheet having thethickness within such a range can be suitably used instead of paper orsynthetic paper for the applications of general printing and informationand packaging.

As the molded product according to the present invention, an aspect inwhich the formed article is a film formed by extrusion molding (blowfilm molding) by an inflation method, that is, what is called aninflation film is desirable. In the case where the formed articleaccording to the present invention is such a thin-thickness inflationfilm, the effect caused by adding the neutralized product of the polymermade of 50% by mole to 100% by mole of the α,β-unsaturated carboxylicacid and 0% by mole to 50% by mole of the other monomer as theconstitutional units as described above is particularly high.Consequently, remarkably stable mechanical properties (for example,tensile strength and elongation) throughout the film can be obtainedwhile the inorganic substance powder such as the calcium carbonateparticles is being highly filled.

In the case of the aspect in which the formed article according to thepresent invention is the inflation film, the film can be a dense film.Alternatively, the inflation film may be a breathable film having gaspermeability that includes a high content of the inorganic substancepowder and is subjected to stretch by air blowing of inflation moldingto form micropores formed in the film layer.

Although not particularly limited, in the case where the inflation filmis the breathable film, the air permeance is 5,000 seconds or more and85,000 seconds or less. The term “air permeance” referred to here is avalue measured in accordance with JIS P8117 (JIS P8117: 2009 “Paper andboard—Determination of air permeance and air resistance (mediumrange)-Gurley method”). More specifically, the time (seconds) when 100cc of air passes through the breathable film having an area of 2,500 mm²in an atmospheric air at 23° C. using a JIS P8117 compliant Gurley typeair permeance meter and this time is determined to be the air permeance(seconds). The number of seconds is measured by a digital auto-counter.The smaller value of the air permeance indicates the higher airpermeability.

The use of the inflation film is not particularly limited and theinflation film can be used for many different applications. Although notparticularly limited, for example, the inflation film is used forsanitary applications, medical applications, healthcare applications,filtration materials, geotextile products, agricultural applications,horticultural applications, clothing, footwear products, bag products,household applications, industrial applications, packaging applications,architecture applications, or construction.

More specific examples of the sanitary applications include surfacelayer materials such as paper diapers for babies, paper diapers foradults, women's sanitary products, and adult incontinence care products,hair removal strips, bandages and wound bandages, disposable bath towelsand face towels, disposable slippers and footwear, surface sheets orcover stocks, and face masks for consumers.

More specific examples of the medical and healthcare applicationsinclude sterilizable medical products, medical packaging, caps such assurgical disposable caps, protective clothing, surgical gowns, surgicalmasks and face masks, surgical gowns, surgical covers, surgical drapes,wraps, packs, sponges, bandages, wipes, bed linens, anti-contaminationgowns, inspection gowns, laboratory white robes, isolation gowns,transdermal drug delivery pads, underpads, treatment packs, heat packs,ostomy bag liners, fixing tapes, incubator mattresses, sterile wrapcold/heat packs, and patches.

More specific examples of the clothing, footwear products, and bagproducts include overcoat fronts, collars, facings, waistbands, coressuch as lower collars, disposable underwear, shoelace pit reinforcementmaterials, athletic shoe and sandal reinforcement materials, shoeconstituent materials such as inner sole linings, bag constituentmaterials, binder compositions, and (washing) precaution labels.

More specific examples of the packaging applications include desiccantpackaging, adsorbent packaging, gift boxes, file boxes, non-woven fabricbags, book covers, envelopes, and home delivery bags.

More specific examples of the architecture and construction applicationsinclude house wraps, asphalt coatings, road and railroad roadbeds, wallcovering linings, acoustic wall coverings, roofing and tile underlays,soil stabilizing materials and road underlays, foundation stabilizingmaterials, sheets for erosion control, irrigation canal construction,drainage systems, frost shields, ponds and irrigation canals, sandintrusion barriers for culvert drainage, and agricultural versatilesheets.

«Method for Producing Formed Article»

The method for producing the formed article according to the presentinvention is not particularly limited as long as the formed article canbe formed in a desired shape. The formed article can be formed andprocessed in any conventionally known methods such as extrusion forming(including extrusion forming by the inflation method), injectionforming, vacuum forming, blow forming, and calendar forming.Furthermore, in the case where the inorganic substance powder-filledresin composition according to the present invention includes thefoaming agent and the formed article of an aspect serving as the foamingbody is obtained, for example, both liquid phase forming methods such asinjection forming, extrusion foaming, and blow foaming or solid phasefoaming such as bead foaming, batch foaming, press foaming, andsecondary foaming under normal pressure may be used as long as thesemethods allow the desired shape to be formed.

The forming temperature at forming cannot be simply determined becausethe temperature varies to a certain extent depending on the formingmethod, the type of the thermoplastic resin to be used, and the like.For example, the forming article formed at a temperature of 180° C. to260° C. and more preferably 190° C. to 230° C. allows the inorganicsubstance powder-filled resin composition according to the presentinvention to have the excellent drawdown property and extension propertyand the formed article having the predetermined shape to be formedwithout locally generating degeneration of the composition.

As the forming, a direct method in which a process for kneading theinorganic substance powder-filled resin composition and a process forforming to the given shape such as a sheet or a film are continuouslycarried out may be used or a method for using a twin-screw extrusionforming machine with a T die system may be used. In the case of formingthe sheet-like product, the sheet-like product can be stretched in auniaxial direction, biaxial directions, or multi-axial directions (forexample, stretching by a tubular method) at the forming or after theforming of the sheet-like product. In the case of the biaxialstretching, the stretching may be sequential biaxial stretching orsimultaneous biaxial stretching.

In the aspect in which the formed article according to the presentinvention is the inflation film, the extrusion molding by the inflationmethod, which is the method for producing the inflation film, is notparticularly limited. For example, the film is desirably treated in ablow ratio (BUR) of 2.0 to 5.0 and more preferably 3.0 to 5.0 in orderto obtain uniform air permeability performance throughout the film.

EXAMPLES

Hereinafter, the present invention will be specifically described withreference to Examples. Examples are described only for the purpose ofexemplifying the specific aspects and embodiments in order to morefacilitate the understanding of the concept and scope of the presentinvention disclosed in the present specification and described in theattached CLAIMS and the present invention is not limited to Examples inany manner.

(Evaluation Methods)

Each physical property in Examples and Comparative Examples describedbelow was evaluated in accordance with the following methods.

(Average Molecular Weight of Polymer)

The weight average molecular weight (Mw) of the neutralized product ofthe polymer made of the α,β-unsaturated carboxylic acid (and the othermonomer) used in Examples and Comparative Examples was measured by gelpermeation chromatography (GPC). The molecular weight is a value whenthe polymer is completely neutralized with sodium hydroxide.

GPC measurement conditions

Model: Waters 510 (manufactured by Nihon Waters K. K.)

Column: TSK gel G5000pwXL, TSK gel G3000pwXL (both are manufactured byTosoh Corporation)

Column temperature: 40° C.

Detector: RI

Solvent: 0.5% sodium acetate-water/methanol (volume ratio 70/30)

Flow rate: 1.0 ml/min

Sample concentration: 0.25% by weight

Injection volume: 200 μl

Standard: Polyoxyethylene glycol (manufactured by Tosoh Corporation; TSKSTANDARD POLYETHYLENE OXIDE)

Data processing unit: SC-8010 (manufactured by Tosoh Corporation)

(Degree of Neutralization)

The degree of neutralization of the neutralized product of the polymermade of the α,β-unsaturated carboxylic acid (and the other monomer) usedin Examples and Comparative Examples was measured using an automatedpotentiometric titrator. More specifically, a predetermined amount of aninorganic base (potassium hydroxide or sodium hydroxide) solution havinga known concentration was added to the neutralized product of thepolymer to obtain a liquid to be measured of which pH is adjusted to thealkaline side. Thereafter, the liquid to be measured was subjected topotential differential titration using an inorganic acid solution(sulfuric acid or hydrochloric acid) to measure the amount of acidgroups in the polymer and the degree of neutralization was calculated.The kind and proportion of the neutralized salt in the neutralizedproduct were determined based on the substance used for neutralizationand the amount of the substance.

(Average Particle Diameter of Inorganic Substance Powder)

The average particle diameter was calculated from the measurement resultof a specific surface area by an air permeation method in accordancewith JIS M 8511 using a specific surface area measurement apparatus TypeSS-100 manufactured by SHIMADZU CORPORATION.

(Tensile Strength and Elongation)

The tensile strength and elongation were measured using AutographAG-100kNXplus (manufactured by SHIMADZU CORPORATION) under conditions of23° C. and 50% RH in accordance with JIS K 7161-2:2014. The testspecimen was formed by cutting out the formed article described belowand had a dumbbell shape. The stretching speed was 10 mm/minute.

(Thickness)

The thickness of the obtained breathable film was measured in accordancewith JIS P7130.

(Product Appearance)

The appearance of the surface of the molded film was visually inspectedand evaluated according to the following evaluation criteria.

[Evaluation criteria]

o: No pinholes, irregularities, scratches, or the like are observed onthe surface at all and the surface has excellent appearance.

Δ: Slightly shallow irregularities are observed on the surface.

x: A fatal defects for a film such as a pinhole are observed on thesurface.

(Materials)

The components used in Examples and Comparative Examples described belowwere as follows.

Thermoplastic resins (A)

A1: Polypropylene homopolymer (manufactured by Prime Polymer Co., Ltd.:Prime Polypro (trade name) E111G, melting point 160° C.)

A2: Polypropylene block copolymer (manufactured by Prime Polymer Co.,Ltd.: Prime Polypro (trade name) BJS-MU, melting point 160° C.)

A3: High-density polyethylene homopolymer (manufactured by KEIYOPOLYETHYLENE CO., LTD.: B5803, melting point 133° C.)

Inorganic Substance Powders (B)

B1: Heavy calcium carbonate particles. Average particle dimeter 0.70 μm(Softon 3200, manufactured by Bihoku Funka Kogyo Co., Ltd.)

B2: Heavy calcium carbonate particles Average particle diameter 0.85 μm(Softon 2600, manufactured by Bihoku Funka Kogyo Co., Ltd.)

B3: Heavy calcium carbonate particles Average particle diameter 1.00 μm(Softon 2200, manufactured by Bihoku Funka Kogyo Co., Ltd.)

B4: Heavy calcium carbonate particles Average particle diameter 1.50 μm(Softon 1500, manufactured by Bihoku Funka Kogyo Co., Ltd.)

B5: Heavy calcium carbonate particles Average particle diameter 3.60 μm(BF100, manufactured by Bihoku Funka Kogyo Co., Ltd.)

B6: Heavy calcium carbonate particles Average particle size 5.00 μm(BF200, manufactured by Bihoku Funka Kogyo Co., Ltd.)

B7: Heavy calcium carbonate particles (without surface treatment)Average particle diameter 8.00 μm (BF300, manufactured by Bihoku FunkaKogyo Co., Ltd.)

B8: Light calcium carbonate particles Average particle diameter 1.5 μm(PC, manufactured by Shiraishi Kaisha Ltd.)

Dispersing agents (C)

C_(A) Neutralized product of polyacrylic acid (weight average molecularweight Mw: 11,500)

C_(A1) neutralization degree: 100.0%, Neutralized salt:Sodium/Magnesium=99.0/1.0

C_(A2) Neutralization degree: 90.0%, Neutralized salt:Sodium/Magnesium=89.5/0.5

C_(A3) Neutralization degree: 70.0%, Neutralized salt:Sodium/Magnesium=69.7/0.3

C_(A4) Neutralization degree: 50.0%, Neutralized salt:Sodium/Magnesium=49.8 0.2

C_(A5) Neutralization degree: 30.0%, Neutralized salt:Sodium/Magnesium=29.3/0.7

C_(A6) Neutralization degree: 50.0%, Neutralized salt:Sodium/Lauryldimethylamine/Magnesium=46.0/3.0/1.0

C_(A7) Neutralization degree: 62.0%, Neutralized salt: Sodium/Propyleneoxide 2-mol adduct of cyclohexylamine=60.0/2.0

C_(A8) Neutralization degree: 47.1%, Neutralized salt: Sodium/Propyleneoxide 4-mol adduct of octadecylamine=47.0/0.1

C_(A9) Neutralization degree: 50.0%, Neutralized salt: Sodium=50.0

C_(A0) Neutralization degree: 0% (polyacrylic acid)

C_(B) Neutralized product of acrylicacid/2-acrylamido-2-methylpropanesulfonic acid copolymer (weight averagemolecular weight Mw: 8,000)

C_(B1) Neutralization degree: 99.8%, Neutralized salt:Sodium/Magnesium=99 0.0/0.8

C_(B2) Neutralization degree: 70.0%, Neutralized salt:Sodium/Magnesium=69.7/0.3

C_(B3) Neutralization degree: 50.0%, Neutralized salt:Sodium/Magnesium=49.8/0.2

C_(B4) Neutralization degree: 30.0%, Neutralized salt:Sodium/Magnesium=29.3/0.7

C_(B5) Neutralization degree: 50.0%, Neutralized salt: Sodium=50.0

C_(B0) Neutralization degree: 0% (polyacrylic acid)

Antistatic agent (D)

D: Lauric acid diethanolamide

Lubricating agent (E)

E: Sodium alkane sulfonate (carbon number of alkyl group (averagevalue)=12)

Antioxidants (F)

F1: Hindered phenolic antioxidant (pentaerythritoltetrakis[3-(3′,5′-di-t-butyl-4′-hydroxyphenyl) propionate]

F2: Tris(2,4-di-t-butylphenyl)phosphite

Example 1

Polypropylene homopolymer A1 as the thermoplastic resin (A), B1described above as the inorganic substance powder (B), and C_(A)3described above as the dispersing agent (C) were used in the blendproportions listed in Table 1. D, E, and F1 and F2 were used as theantistatic agent, the lubricating agent, and the antioxidants inappropriate amounts, respectively and the total amount thereof was setto 6.0 parts by mass. The blend amount of the antistatic agent,lubricating agent, and antioxidants were the same in other Examples andComparative Examples described below except in Example 24. In Table 1,the numerical values of each component are values in parts by mass.

The film was prepared by an inflation film extrusion line (a circulardie having a diameter of 60 mm, a die gap of 1.2 mm, a screw diameter of30 mm, and a L/D ratio of 30). The film was treated in a BUR (blow-upratio) of 3.0 to retain the frostline height at a height of 16 cm (thedistance from the die).

In the extruder, the temperature of each zone was set to 190° C. to 230°C. The rotation speed of the extruder was always maintained at 60 rpmand the basis weight of the film was set to 35 g/m² by appropriateadjustment of the line speed. The cooling air flow was adjustedaccordingly to keep the frostline at the same position.

The evaluation results of the tensile strength, elongation, thickness,and product appearance of the obtained film are listed in Table 2.

Examples 2 and 3 and Reference Examples 1 and 2

Films were prepared by the inflation method in the same manner as themanner in Example 1 except that the blending amount of C_(A3) as thedispersing agent (C) used in Example 1 was changed as listed in Table 1.The evaluation results of the tensile strength, elongation, thickness,and product appearance of the obtained films are listed in Table 2.

Comparative Example 1

A Film was prepared by the inflation method in the same manner as themanner in Example 1 except that C_(A3) as the dispersing agent (C) usedin Example 1 was not blended. The evaluation results of the tensilestrength, elongation, thickness, and product appearance of the obtainedfilms are listed in Table 2.

Examples 4 to 16 and Comparative Examples 2 and 3

Films were prepared by the inflation method in the same manner as themanner in Example 2 except that each of the dispersing agents listed inTable 1 was used instead of C_(A)3 as the dispersing agent (C) used inExample 2. The evaluation results of the tensile strength, elongation,thickness, and product appearance of the obtained films are listed inTable 2.

Examples 17 to 23

Films were prepared by the inflation method in the same manner as themanner in Example 2 except that each of B2 to B8 was used instead of B1as the inorganic substance powder (B) used in Example 2. The evaluationresults of the tensile strength, elongation, thickness, and productappearance of the obtained films are listed in Table 2.

Example 24

A film was prepared by the inflation method in the same manner as themanner in Example 2 except that the antistatic agent (D), thelubricating agent (E), and the antioxidant (F) used in Example 2 werenot blended. The evaluation results of the tensile strength, elongation,thickness, and product appearance of the obtained films are listed inTable 2.

Examples 25 and 26

Films were prepared by the inflation method in the same manner as themanner in Example 2 except that each of A2 and A3 was used instead of A1as the thermoplastic resin (A) used in Example 2. The evaluation resultsof the tensile strength, elongation, thickness, and product appearanceof the obtained films are listed in Table 2.

Examples 27 to 29

Films were prepared by the inflation method in the same manner as themanner in Example 2 except that the blend amounts of the thermoplasticresin (A) and inorganic substance powder (B) in Example 2 were changedas listed in Table 1. The evaluation results of the tensile strength,elongation, thickness, and product appearance of the obtained films arelisted in Table 2.

TABLE 1 Thermo- Inorganic Total amount plastic substance Dispersing ofD, E, F1, resin (A) powder (B) agent (C) and F2 (part by (part by (partby (part by mass) mass) mass) mass) Comparative A1/40 B1/60 6.0 Example1 Reference A1/40 B1/60 C_(A3)/1 6.0 Example 1 Example 1 A1/40 B1/60C_(A3)/4 6.0 Example 2 A1/40 B1/60 C_(A3)/7 6.0 Example 3 A1/40 B1/60C_(A3)/10 6.0 Reference A1/40 B1/60 C_(A3)/15 6.0 Example 2 Example 4A1/40 B1/60 C_(A1)/7 6.0 Example 5 A1/40 B1/60 C_(A2)/7 6.0 Example 6A1/40 B1/60 C_(A4)/7 6.0 Example 7 A1/40 B1/60 C_(A5)/7 6.0 Example 8A1/40 B1/60 C_(A6)/7 6.0 Example 9 A1/40 B1/60 C_(A7)/7 6.0 Example 10A1/40 B1/60 C_(A8)/7 6.0 Example 11 A1/40 B1/60 C_(A9)/7 6.0 ComparativeA1/40 B1/60 C_(A0)/7 6.0 Example 2 Example 12 A1/40 B1/60 C_(B1)/7 6.0Example 13 A1/40 B1/60 C_(B2)/7 6.0 Example 14 A1/40 B1/60 C_(B3)/7 6.0Example 15 A1/40 B1/60 C_(B4)/7 6.0 Example 16 A1/40 B1/60 C_(B5)/7 6.0Comparative A1/40 B1/60 C_(B0)/7 6.0 Example 3 Example 17 A1/40 B2/60C_(A3)/7 6.0 Example 18 A1/40 B3/60 C_(A3)/7 6.0 Example 19 A1/40 B4/60C_(A3)/7 6.0 Example 20 A1/40 B5/60 C_(A3)/7 6.0 Example 21 A1/40 B6/60C_(A3)/7 6.0 Example 22 A1/40 B7/60 C_(A3)/7 6.0 Example 23 A1/40 B8/60C_(A3)/7 6.0 Example 24 A1/40 B1/60 C_(A3)/7 — Example 25 A2/40 B1/60C_(A3)/7 6.0 Example 26 A3/40 B1/60 C_(A3)/7 6.0 Example 27 A1/30 B1/70C_(A3)/7 6.0 Example 28 A1/20 B1/80 C_(A3)/7 6.0 Example 29 A1/10 B1/90C_(A3)/7 6.0

TABLE 2 Tensile Thick- strength Elongation ness Product (MPa) (%) (μm)appearance Remarks Comparative 24 260 90-100 Δ Thickness Example 1varies Reference 30 300 100 ○ — Example 1 Example 1 31 300 100 ○ —Example 2 32 300 100 ○ — Example 3 31 310 100 ○ — Reference 30 310 100 ○— Example 2 Example 4 32 320 100 ○ — Example 5 31 310 100 ○ — Example 631 310 100 ○ — Example 7 32 320 100 ○ — Example 8 31 320 100 ○ — Example9 32 310 100 ○ — Example 10 31 300 100 ○ — Example 11 32 310 100 ○ —Comparative 25 250 95-105 Δ Thickness Example 2 slightly varies Example12 31 300 100 ○ — Example 13 31 320 100 ○ — Example 14 32 310 100 ○ —Example 15 31 320 100 ○ — Example 16 32 300 100 ○ — Comparative 25 25095-105 Δ Thickness Example 3 slightly varies Example 17 31 320 100 ○ —Example 18 31 310 100 ○ — Example 19 31 310 100 ○ — Example 20 32 300100 ○ — Example 21 31 310 100 ○ — Example 22 31 300 100 ○ — Example 2332 320 100 ○ — Example 24 31 320 100 ○ — Example 25 30 300 100 ○ —Example 26 29 320 100 ○ — Example 27 31 300 100 ○ — Example 28 32 310100 ○ — Example 29 31 300 100 ○ —

As can be seen from the results listed in Table 2, in Examples accordingto the present invention, even in a high blending amount of theinorganic substance powder, the inorganic substance powder was uniformlydispersed in the resin component without uneven distribution, whichallowed the inflation molding to be stably performed without anyproblem, and the formed article having excellent appearance of theformed article and excellent mechanical properties was able to beobtained.

Example 30

The inorganic substance powder-blended thermoplastic resin compositionhaving the same composition as the resin composition in Example 1 wasformed into a sheet at a temperature of 220° C. using a twin-screwextruder with a T-die and thereafter the obtained sheet wasvacuum-formed into a container product having a deep-dish shape at atemperature of 220° C. As a result, as similar to the case of Example 1,the container product having sufficient mechanical properties andexcellent appearance was able to be produced without causing anytroubles at the time of the processing.

1. An inorganic substance powder-filled resin composition comprising: athermoplastic resin and inorganic substance powder in a mass ratio of50:50 to 10:90, wherein a neutralized product of a polymer made of 50%by mole to 100% by mole of an α,β-unsaturated carboxylic acid and 0% bymole to 50% by mole of other monomer as constitutional units is added.2. The inorganic substance powder-filled resin composition according toclaim 1, wherein the neutralized product of the polymer made of 50% bymole to 100% by mole of the α,β-unsaturated carboxylic acid and 0% bymole to 50% by mole of the other monomer as the constitutional units isadded in an amount of 3% by mass to 10% by mass relative to the entirecomposition.
 3. The inorganic substance powder-filled resin compositionaccording to claim 1, wherein the α,β-unsaturated carboxylic acid is(meth)acrylic acid, and a weight average molecular weight of theneutralized product of the polymer made of 50% by mole to 100% by moleof the α,β-unsaturated carboxylic acid and 0% by mole to 50% by mole ofthe other monomer as the constitutional units is 1,000 to 100,000. 4.The inorganic substance powder-filled resin composition according toclaim 1, wherein the other monomer is an aromatic ethylenicallyunsaturated monomer, an alkyl (meth)acrylate, and/or a sulfogroup-containing monomer.
 5. The inorganic substance powder-filled resincomposition according to claim 1, wherein the inorganic substance powderis calcium carbonate particles.
 6. The inorganic substance powder-filledresin composition according to claim 1, wherein an average particlediameter of the inorganic substance powder in accordance with an airpermeation method is 0.5 μm or more and 13.5 μm or less.
 7. Theinorganic substance powder-filled resin composition according to claim1, wherein the inorganic substance powder is not subjected to surfacetreatment.
 8. A formed article comprising an inorganic substancepowder-filled resin composition, the resin composition comprising: athermoplastic resin and inorganic substance powder in a mass ratio of50:50 to 10:90, wherein a neutralized product of a polymer made of 50%by mole to 100% by mole of an α,β-unsaturated carboxylic acid and 0% bymole to 50% by mole of another monomer as constitutional units is added.9. The formed article according to claim 8, wherein the formed articleis an inflation film.
 10. The inorganic substance powder-filled resincomposition according to claim 2, wherein the α,β-unsaturated carboxylicacid is (meth)acrylic acid, and a weight average molecular weight of theneutralized product of the polymer made of 50% by mole to 100% by moleof the α,β-unsaturated carboxylic acid and 0% by mole to 50% by mole ofthe other monomer as the constitutional units is 1,000 to 100,000. 11.The inorganic substance powder-filled resin composition according toclaim 2, wherein the other monomer is an aromatic ethylenicallyunsaturated monomer, an alkyl (meth)acrylate, and/or a sulfogroup-containing monomer.
 12. The inorganic substance powder-filledresin composition according to claim 3, wherein the other monomer is anaromatic ethylenically unsaturated monomer, an alkyl (meth)acrylate,and/or a sulfo group-containing monomer.
 13. The inorganic substancepowder-filled resin composition according to claim 2, wherein theinorganic substance powder is calcium carbonate particles.
 14. Theinorganic substance powder-filled resin composition according to claim3, wherein the inorganic substance powder is calcium carbonateparticles.
 15. The inorganic substance powder-filled resin compositionaccording to claim 4 wherein the inorganic substance powder is calciumcarbonate particles.
 16. The inorganic substance powder-filled resincomposition according to claim 2, wherein an average particle diameterof the inorganic substance powder in accordance with an air permeationmethod is 0.5 μm or more and 13.5 μm or less.
 17. The inorganicsubstance powder-filled resin composition according to claim 5, whereinan average particle diameter of the inorganic substance powder inaccordance with an air permeation method is 0.5 μm or more and 13.5 μmor less.
 18. The inorganic substance powder-filled resin compositionaccording to claim 13, wherein an average particle diameter of theinorganic substance powder in accordance with an air permeation methodis 0.5 μm or more and 13.5 μm or less.
 19. The inorganic substancepowder-filled resin composition according to claim 14, wherein anaverage particle diameter of the inorganic substance powder inaccordance with an air permeation method is 0.5 μm or more and 13.5 μmor less.
 20. The inorganic substance powder-filled resin compositionaccording to claim 15, wherein an average particle diameter of theinorganic substance powder in accordance with an air permeation methodis 0.5 μm or more and 13.5 μm or less.